Simultaneous measurement of refractive index and temperature based on SPR in D-shaped MOF

Abstract

A surface plasmon resonance (SPR) sensor based on D-shaped microstructured optical fiber (MOF) is proposed to realize the simultaneous measurement of refractive index (RI) and temperature. The D-shaped flat surface coated with a gold layer is in direct contact with analyte as a sensing channel of RI, and one of the air holes near the fiber core is filled with chloroform to detect temperature. Two separate channels and birefringence caused by the asymmetric structure can distinguish the variations of RI and temperature independently, thus completely solving the cross-sensitivity problem. This is the first time to realize the simultaneous measurement of multiple parameters without matrix equations, to the best of our knowledge. Results show that the y-polarized peak supported by channel I only shifts with RI variation and is unaffected by the temperature floating. Similarly, the x-polarized peak supported by channel II is only influenced by the change of temperature in the external environment. The effect of gold layer thickness is investigated numerically, and the sensor sensitivity is identified both in wavelength and amplitude interrogations. This work is very helpful for the design and implementation of a highly sensitive, real-time, and distributed SPR sensor for multi-parameter measurement applications.

Plasmonic Refractive Index Sensors Based on One- and Two-Dimensional Gold Grating on a Gold Film

“…The electric field enhancement [6][7][8] and strong absorption [9,10] caused by the local surface plasmons are widely used in surface-enhanced Raman scattering [11][12][13] and enhanced absorption [14,15]. In addition, the unique optical properties of surface plasmons have a wide range of applications in photocatalysis [16][17][18][19][20], absorber [21][22][23][24], photolithography [25][26][27][28], filter [29,30], optical data storage [31,32], and other fields [33][34][35][36]. At present, one of the most important researches focusing on surface plasmons is refractive index sensing [37][38][39][40][41][42].…”

Reflective Fiber Surface Plasmon Resonance Sensor for High-Sensitive Mercury Ion Detection

“…Besides, the variation of temperature will change the physicochemical properties of the CS/PAA sensitive film and the sensing properties of the SPR sensor, which will then induce measurement error in the mercury ion sensor. To solve this temperature crosstalk problem, one feasible method is to measure the mercury ion concentration and temperature simultaneously, and then compensate the influence of temperature [23,24]. We will focus on this problem in the future.…”

A Reconfigurable Surface-Plasmon-Based Filter/Sensor Using D-Shaped Photonic Crystal Fiber

“…Photonic crystal fibers (PCF) are a new type of fiber that has a flexible structure and various unique features, such as high nonlinearity [1], engineered dispersion profile over the region of interest [2,3], high birefringence [4], endless single mode, low transmission loss [2][3][4][5] and easy filling of materials in fiber [6][7][8]. PCF has been extended to plasmonic devices by filling them with various metals, such as gold [9][10][11][12][13], silver [14,15], copper [16] and titanium [17]. Surface plasmon (SP) develops at the metal/dielectric interface when plasmonic materials are exposed to electromagnetic waves due to the collective oscillations of conduction electrons [18].…”